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From:   Dave Hansen <dave.hansen@intel.com>
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On 9/18/23 09:51, Joseph, Jithu wrote:
> 
> On 9/18/2023 9:29 AM, Ilpo Järvinen wrote:
> 
>> In this case it is not just about the bitfield itself nor the bit 
>> allocation order but sharing the storage unit with another member, and to 
>> further complicate things, members have different alignment requirement 
>> too (32-bit aligned u8 followed by u32 bitfield).
>>
> I too verified that the size of the whole structure matches that of MSR  64 bits (8 bytes). 
> 
> Initially when IFS scan was added the  all MSR structure members were  bit-fields, later there was a suggestion to
> use basic C types if applicable during subsequent Array BIST patch series. I followed this approach with the  current patch series . 
> 
> I will change the current series to use all bit-field MSR structures in v2, given mixing basic types and bitfields is a a source of confusion

That's the wrong direction. :)

What is more obviously correct.  This:

	struct {
		u16	valid_chunks;
		u16	total_chunks;
		u8	error_code;
		u8	rsvd1;
		u8	rsvd2;
		u8	rsvd3;
	};

or this:

	struct {
		u16	valid_chunks;
		u16	total_chunks;
		u8	error_code;
		u32	error_code	:8;
		u32	rsvd		:24;
	};

?